/*
 * Copyright 2018 Red Hat, Inc. and/or its affiliates.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.kie.internal.command;

import java.util.function.Function;

import org.kie.api.runtime.Context;

public interface RegistryContext extends Context {

    <T> RegistryContext register(Class<T> clazz, T instance);

    <T> T lookup(Class<T> clazz);

    default <T> T computeIfAbsent(Class<T> clazz, Function<? super Class<T>, ? extends  T> mappingFunction) {
        T element = lookup(clazz);
        if (element == null) {
            element = mappingFunction.apply(clazz);
            register(clazz, element);
        }
        return element;
    }

    ContextManager getContextManager();

    static RegistryContext create() {
        try {
            return (RegistryContext) Class.forName( "org.drools.commands.impl.ContextImpl" ).getConstructor().newInstance();
        } catch (Exception e) {
            throw new RuntimeException("Unable to instance RegistryContext, please add org.drools:drools-commands to your classpath", e);
        }
    }
}
